Hello,
Can we impose if then else into list comprehension ?
Like we do in lambda-map form:
This code change None into 0
L = [None, 12]
R = map(lambda x: (x==None and [0] or x)[0], L) # [0,12]
pujo
4  1107 
I wasn't aware that python supported "if then else".
Hello,
On 24 Jun 2005 11:45:14 -0700, aj****@gmail.com wrote: Hello,
Can we impose if then else into list comprehension ?
Like we do in lambda-map form:
This code change None into 0
L = [None, 12]
R = map(lambda x: (x==None and [0] or x)[0], L) # [0,12]
Do you mean:
[(x==None and [0] or [x])[0] for x in L]
or [{None:0}.get(x,x) for x in L]
or [x or 0 for x in L]
Well, the third solution doesn't exactly fit the specification but may
be easier to read.
Christophe
On Fri, 24 Jun 2005 21:04:15 +0200, Christophe Delord wrote: Hello,
On 24 Jun 2005 11:45:14 -0700, aj****@gmail.com wrote:
Hello,
Can we impose if then else into list comprehension ?
Like we do in lambda-map form:
This code change None into 0
L = [None, 12]
R = map(lambda x: (x==None and [0] or x)[0], L) # [0,12]
Do you mean:
[(x==None and [0] or [x])[0] for x in L]
or [{None:0}.get(x,x) for x in L]
or [x or 0 for x in L]
Well, the third solution doesn't exactly fit the specification but may
be easier to read.
Or, more generally,
[0 for x in L if x is None]
which doesn't solve the asked-for question, but is a useful feature.
--
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